This invention relates generally to laminated multi-layered composites, and more particularly, to multi-layered composites having a liner layer for providing chemical and corrosion protection to concrete structures.
Protection of concrete structures, such as, holding tanks, containment tanks and sumps, and trenches, from exposure to corroding chemicals is an ongoing problem in, for example, the chemical industry. A number of means of protecting concrete structures are currently in use; however, most of the current protection schemes have serious drawbacks. Epoxy coatings have been used for concrete protection. Failure of the coating due to concrete movement can cause leaks that can result in concrete deterioration. Also, Epoxy coatings are brittle and have very little impact and/or structural strength.
Single skin thermoplastic anchor liners have also been used to protect concrete. These liners are anchored into the concrete during the concrete pouring process. They do not have any structural strength and are not self supportive. Because of the single skin construction, these liners can be easily damaged resulting in concrete exposure to corrosive chemicals. Single skin thermoplastic anchor liners require complicated, costly, and time consuming installation. Further, if there are air pockets between the liner and the concrete, there is a high probability of liner failure due to an expansion of the air pocket which can shear the anchor off the liner permitting weld movement and possible weld failure.
Acid bricks have also been used to protect concrete. Acid bricks are costly and very time consuming to install, and require specially trained installers. Acid bricks are brittle and have low impact strength and very low shear strength. Also, the acid bricks can crack due to movement of the concrete foundations.